[OE-core] sstate reuse for -native, -cross across different host glibc version, how to make it work?

[McClintock Matthew-B29882]

On Fri, Mar 23, 2012 at 7:41 AM, Richard Purdie
<richard.purdie at linuxfoundation.org> wrote:
> On Fri, 2012-03-23 at 13:22 +0100, Koen Kooi wrote:
>> I turned on sstate mirroring for angstrom recently and I'm getting
>> reports of build failures due to missing GLIBC_2.14 symbols:
>>
>> arm-angstrom-linux-gnueabi-gcc: /lib/x86_64-linux-gnu/libc.so.6:
>> version `GLIBC_2.14' not found (required by
>> arm-angstrom-linux-gnueabi-gcc)
>>
>> The sstate tarballs are built on a Fedora16 VM and the breakage occurs
>> when it being used on systems with an older c library (e.g. debian).
>> To get rid of this problem there are multiple options, but I think the
>> 2 most obvious are:
>>
>> 1) inject host distroname and distroversion into the checksums
>> 2) build everything against a native libc
>>
> 3) Use an older version on the VM which is the oldest distro you plan to
> build against.
>
>> Would it be appropriate to get 1) into oe-core before the branchpoint?
>
> We've talked about this and its been on the "to fix" list but nobody has
> got around to it. Its hard as we need to come up with something that
> isn't going to kill performance of the checksum calculations. A cat
> operation on a few files for each checksum for example isn't
> appropriate. We may need to do something at the bitbake level as there
> is also the issue of checksuming local files such as those in file://
> urls and including that in the sstate checksums.
>
> So whilst I'd love to see fixes for these and they are bugfixes, they're
> going to have to be well written patches and its late in cycle for
> invasive changes :(.

Can't you just inject a variable into native.bbclass:

LIBC_DEP = `ldd /bin/sh | grep libc`

-M